Pericardial effusion is a buildup of fluid in the pericardium, a fibrous sac that surrounds the heart. Normally there is a small amount of fluid between the two thin layers of the pericardium, but certain medical problems like autoimmune diseases, cancer, injuries or infections can cause too much fluid to build up, leading to uncomfortable or even life-threatening cardiovascular symptoms.

Depending on the severity of the buildup, pericardial effusion may be treatable with medicines. If the health care team determines that it’s necessary to drain the excess fluid, they may recommend a procedure called pericardiocentesis, which uses a needle and small catheter to drain the fluid. This treatment may need to be repeated if fluid buildup continues.

Percutaneous balloon pericardiotomy is another catheter-guided draining procedure, but it uses a balloon to create a small hole in the pericardium to ease draining.

When draining procedures are ineffective, a more invasive procedure called a pericardiectomy may be required, during which a surgeon removes part or all of the pericardium. Occasionally, open heart surgery is needed to drain fluid or repair the pericardium.